<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>三角形</title>
    <style>
        div{
            width:0;
            height:0;
            border-top:150px black solid;
            border-bottom:150px transparent solid;
            border-right:150px transparent solid;
            border-left:150px transparent solid;

        }
    </style>
</head>
<body>
<div></div>
<script>

</script>
</body>
</html>